The invention relates to an apparatus for reducing the concentration of pollutants in the exhaust emissions of an internal combustion engine, particularly an engine driving an electric generator on a boat. The invention is particularly adapted for connecting to the exhaust manifold of a marine electric generator engine.
It is well known that internal combustion engines produce an exhaust emission containing pollutants that are harmful to the environment. Such pollutants include carbon monoxide, carbon dioxide and various hydrocarbons. There are many inventions for reducing the concentration of such pollutants in engine exhaust emissions. For example, U.S. Pat. Nos. 5,410,871 and 5,419,123 each disclose emission control devices particularly suited for reducing pollutant levels in automobile exhaust emissions.
Pollution control for marine electric generator engines presents a unique set of challenges that have not been sufficiently addressed by the prior art. Houseboats and large cruisers typically have an electric generator for powering air conditioning, stereos, appliances and the like. Electricity is generated by a conventional internal combustion engine that produces an exhaust emission containing a relatively high concentration of pollutants. Typically, the concentration of pollutants is higher than that given off by automobile engines due to the lack of required anti-pollution equipment.
Such marine generators are commonly operated when the boat is stationary, and thus the pollutants are emptied into a single concentrated area in the water that is to where people may be swimming. The collection of toxic pollutants such as carbon monoxide near swimmers, particularly children, presents a potentially life-threatening situation making effective pollution control of marine generator engines critical. Emission control devices, such as the ones disclosed in U.S. Pat. Nos. 5,410,871 and 5,419,123 can get extremely hot during operation-over 300xc2x0 Fahrenheit which can lead to overheating and fire. The danger of fire on a boat is just as life-threatening as the presence of poisonous gases, and therefore a pollution control device for a marine generator engine must be highly resistant to overheating as well as extremely effective in reducing poisonous gases. Furthermore, pollution control for a marine generator engine requires a device that is capable of eliminating the substantially higher concentrations of pollutants contained in the gaseous emissions of marine generator engines.
In an effort to overcome and eliminate the aforementioned problems, the present invention was conceived.
Therefore it is an object of the present invention to provide an apparatus and method for reducing the relatively high concentration of pollutants in the exhaust emissions of marine electric generator engines.
It is another object of the invention to provide an apparatus resistant to overheating that is capable of reducing the concentration of pollutants in the exhaust emissions of an internal combustion engine.
It is yet another object of the present invention to provide a pollution control apparatus that can be mated with a marine electric generator.
These and other objectives of the present invention are achieved by providing a system for reducing pollutants in internal combustion engine emissions having a treatment chamber including an intake opening and an exhaust opening at opposing lateral ends of the treatment chamber, the intake opening for receiving a stream of gaseous emissions from the engine, and the exhaust opening for exiting the gaseous emission stream from the chamber. A metal tube is disposed within the treatment chamber, and an electrode is disposed within the metal tube in spaced apart relation to the metal tube. The electrode is encircled by the metal tube so that, upon applying a voltage to the electrode, an arc is generated across the space between the electrode and the metal tube, the metal tube providing potential points of contact for the arc around the periphery thereof. The system further includes means for generating the arcing from the electrode to the metal tube at a predetermined frequency to promote a chemical reaction that reduces the concentration of pollutants in the stream within the treatment chamber, the arc generating means having a voltage source operatively connected to the electrode and a pulsing mechanism operatively configured with the voltage source to cause the voltage supplied to the electrode to be pulsed at the predetermined frequency.
According to one preferred embodiment of the invention, the metal tube is perforated to allow passage of the stream of gaseous emissions therethrough.
According to another preferred embodiment of the invention, the electrode is a threaded rod.
According to yet another preferred embodiment of the invention, the metal tube and electrode are disposed within the treatment chamber perpendicularly to the longitudinal axis of the treatment chamber. First and second baffles are disposed within the treatment chamber proximate the metal tube. The baffles are positioned on opposite sides of the metal tube at approximately forty-five degree angles relative to the metal tube whereby the baffles direct the stream of gaseous emissions toward the metal tube.
According to yet another preferred embodiment of the invention, the system includes a manifold having first and second openings at opposing lateral ends of the manifold, an inlet port for receiving a flow of water, and an outlet port for exiting the flow of water. At least a portion of the treatment chamber is contained within the manifold, and is positioned such that the intake opening is linearly aligned with the first opening and the exhaust opening is linearly aligned with the second opening. The treatment chamber and the manifold define a space wherein a flow of water cools the treatment chamber. The system further includes water supply means connected to the inlet port for introducing the flow of water into the manifold.
According to yet another preferred embodiment of the invention, the treatment chamber is longer than the manifold and includes a first segment having the intake opening and containing the metal tube proximate the intake opening. The first segment extends outward from the first opening of the manifold.
According to yet another preferred embodiment of the invention, the treatment chamber includes a second segment downstream from the first segment and having the exhaust opening. The second segment is contained within the manifold and cooled by the flow of water.
According to yet another preferred embodiment of the invention, the system includes a section of porous chemical substrate disposed within the second segment of the treatment chamber for promoting the chemical reaction.
According to yet another preferred embodiment of the invention, the system includes a plate covering a substantial portion of the exhaust opening to restrict passage of the stream of gaseous emissions therethrough.
According to yet another preferred embodiment of the invention, the pollutants include carbon monoxide, and the chemical substrate section includes an oxidizing agent for oxidizing carbon monoxide as it passes through the substrate.
According to yet another preferred embodiment of the invention, the chemical substrate section includes one or more of the group consisting of silica, sodium oxide, alumina, magnesia, calcium oxide, and iron oxide.
According to yet another preferred embodiment of the invention, the system is configured to be mateable with an exhaust system of a conventional marine electric generator engine.
According to yet another preferred embodiment of the invention, the water supply means is integral with the generator engine.
According to yet another preferred embodiment of the invention, the water supply means includes a radiator.
According to yet another preferred embodiment of the invention, the system includes a supplemental air source connected to the treatment chamber for supplying air for diluting the stream of gaseous emissions within the treatment chamber.
According to yet another preferred embodiment of the invention, the supplemental air source includes an air pump mounted in place of the generator engine""s alternator. The air pump supplies air to the treatment chamber at a rate in the range of fifteen to twenty-three cubic feet per minute.
According to yet another preferred embodiment of the invention, the system includes a treatment chamber having intake and exhaust openings at opposing lateral ends of the treatment chamber, the intake opening for receiving a stream of gaseous emissions from an engine, and the exhaust opening for exiting the stream from the chamber. A supplemental air source is connected to the treatment chamber for supplying air for diluting the stream of gaseous emissions within the treatment chamber. A conductor having a predetermined high electric potential is disposed within the treatment chamber. An electrode is disposed in spaced apart relation to the conductor and has an opposite high electric potential so that, upon applying a voltage to the electrode, an arc is generated across the space between the electrode and the conductor. The system includes means for generating the arcing from the electrode to the metal tube at a predetermined frequency to promote a chemical reaction reducing the concentration of pollutants in the stream within the treatment chamber, the arc generating means including a voltage source operatively connected to the electrode and a pulsing mechanism operatively configured with the voltage source causing the voltage supplied to the electrode to be pulsed at the predetermined frequency.
According to yet another preferred embodiment of the invention, the conductor is a metal tube encircling the electrode so that, upon applying a voltage to the electrode, an arc is generated across the space between the electrode and the metal tube. The metal tube provides potential points of contact for the arc around the periphery thereof.
According to yet another preferred embodiment of the invention, the pollutants include one or more substances selected from the group consisting of carbon monoxide and hydrocarbons, and the chemical reaction comprises a conversion of a substantial portion of the pollutants to one or more substances selected from the group consisting of oxygen, water, hydrogen and carbon dioxide.
According to yet another preferred embodiment of the invention,the system is made of stainless steel.
According to yet another preferred embodiment of the invention, the system includes a section of porous chemical substrate disposed within the treatment chamber for promoting the chemical reaction.
According to yet another preferred embodiment of the invention, the chemical substrate section is disposed downstream from the metal tube so that the stream of gaseous emissions passing proximate the metal tube subsequently passes through the chemical substrate.
An embodiment of the method of reducing pollutants in the gaseous emissions of a marine electric generator according to the invention includes the steps of providing a treatment chamber having an intake and exhaust openings at opposing lateral ends of the chamber, a metal tube disposed within the treatment chamber containing an electrode disposed in spaced apart relation to the metal tube and having an opposite high electric potential so that, upon applying a voltage to the electrode, an arc is generated across the space between the electrode and the metal tube, and a porous chemical substrate disposed within the treatment chamber downstream from the metal tube. The intake opening is connected to the exhaust system of the marine electric generator engine so that a stream of gaseous emissions passes from the exhaust system through the intake opening into said treatment chamber. A supplemental stream of air is supplied to the treatment chamber to dilute the stream of gaseous emissions within the treatment chamber, and a voltage is pulsed at a predetermined frequency to the electrode to generate arcing from the electrode to the metal tube at the predetermined frequency to promote a chemical reaction with the stream of gaseous emissions as the stream passes proximate the metal tube. The chemical reaction reduces the concentration of pollutants in the gaseous emission stream.
Another embodiment of the method of reducing pollutants in the gaseous emissions of a marine electric generator according to the invention includes the steps of providing a device comprising a treatment chamber having an intake and exhaust openings at opposing lateral ends of the treatment chamber, a metal tube disposed within the treatment chamber containing an electrode disposed in spaced apart relation to the metal tube and having an opposite high electric potential so that, upon applying a voltage to the electrode, an arc is generated across the space between the electrode and the metal tube, a porous chemical substrate disposed within the treatment chamber downstream from the metal tube, and, a manifold having first and second openings at opposing lateral ends of the manifold, the manifold further including an inlet port for receiving a flow of water and an outlet port for exiting the flow of water. At least a portion of the treatment chamber is contained within the manifold, and the treatment chamber is positioned such that the intake opening is linearly aligned with the first opening and the exhaust opening is linearly aligned with said second opening. The treatment chamber and the manifold define a space wherein the flow of water cools the treatment chamber.
The intake opening is connected to the exhaust system of the marine electric generator engine so that a stream of gaseous emissions passes from the exhaust system through the intake opening into the treatment chamber. A supplemental stream of air is supplied to the treatment chamber to dilute the stream of gaseous emissions within the treatment chamber.
A voltage is pulsed at a predetermined frequency to the electrode to generate an arc from the electrode to the metal tube at the predetermined frequency to promote a chemical reaction with the stream of gaseous emissions as the stream passes proximate the metal tube. The chemical reaction reduces the concentration of pollutants in the stream. A water source is connected to the inlet port and supplies the flow of water into the manifold through the inlet port for cooling the treatment chamber.
Yet another embodiment of the method of reducing pollutants in the gaseous emissions of a marine electric generator according to the invention includes the step of providing a chemical substrate that promotes a chemical reaction with the stream of gaseous emissions further reducing the concentration of pollutants therein as the stream passes through the substrate.